The invention relates to a hydraulic emergency control.
A hydraulic emergency control for an electronically controlled, continuously variable transmission (continuously variable transmission, CVT) is described in DE-42 34 103 A1. The CVT transmission which is preferably employed in motor vehicles, has a control for emergency driving operations which, when the electrical control of normal driving operations fails, causes a switching position with a high gear ratio in order to provide more advantageous restart and start-up conditions. Among other things, the ratio of primary to secondary clamping force between the pulling means and the pairs of beveled disks is maintained constant by means of this control through an intermediate gear range. In the intermediate gear range the gear ratio changes as a function of the torque requirements of the power take-off shaft. With a high demand a high gear ratio is selected, while a low gear ratio is set with a low demand. The means required for this are recited in the description of FIGS. 1 and 2.